Electronic dictionaries considered harmful
My impression? From a professional teacher of English? "Teh sux."
Behold one of the toys of the Vietnamese nouveau riche - the bilingual electronic dictionary. They are popular in my English classes. They're slim enough to be held with one hand, and even come with a plastic case for extra durability. They translate from Vietnamese to other languages, and retranslate back as well. Several flavors are available for the consumer: Vietnamese-English, Vietnamese-French, and even Vietnamese-Chinese. Some models even offer voice, so you can hear the word spoken. They can be purchased for a price of just over two hundred American dollars!
At this point, you may be forgiven for thinking "How poor is the country again?" There are several ways of estimating poverty. You can rely on a glance around the street ("Fuckin' 'ell! They're poor!"). Or you can use hard econometric data calculated by the IMF. I prefer numbers to impressions, so I'll use the common measure of average GDP per capita. When you add up the value of all goods and services produced within this nation in a given year, and divide by the population, what does it come to? That gives you a nice, measurable figure, and as of 2005, it was $612 USD. (I'm not adjusting for PPP; no adjustment is necessary.) My point of this is that these devices should be pretty damned bloody good if they cost a third of Việt Nam's average yearly GDP. In Australia, a third of the average income could buy you a pretty decent second hand car.
Personally, and (more important) professionally, I think the students have been gypped. They have been ripped off. They have been taken for a ride. They have been rolled like a sex tourist looking for a "massage" in Phạm Ngũ Lão. They've been deluded by the presentation - a nice new-fangled (for this nation) electronic device, often packaged as "All-American" for greater envy from their peers. The problem is that the content is not up to spec, and that's what you buy a dictionary for, isn't it?
Well, if these machines aren't 99.98% accurate, and I'd expect no less, then they're not worth buying at all, and certainly not for these prices. As Woody Allen as said to Stanley Kubrick "You can't polish a turd", and these are $200 turds indeed. But as Mr. Kubrick riposted back, "You can if you freeze them". It seems that congealing these pieces of poo in metal and plastic is sufficient to sell them to the masses.
What are my problems with these infernal machines? The major reason - and sufficient for one teacher of my acquaintance to blackball them - is that there are no example sentences. When students look up the meaning of a word in one language, they will get the equivalent or equivalents in the opposite tongue. That is necessary for a dictionary but insufficient to stop translation problems.
Let me illustrate with a purely hypothetical example. One of my students wants to know what "xanh" means in English. He turns on the device, and types the word in. The machine returns the following English synonyms back: (1): "blue"; (2): "green". Unfortunately, examples are not provided like "The sky is blue" and "Plants are green". So the student makes sentences like "The sky is green" and "Plants are blue" instead. In practice, even the rawest neophyte generally grasps the distinction between "green" and "blue", but still - a good dictionary should be careful in distinguishing these words anyway on principle.
This brings us on the related problem of "usage". How do native English speakers actually use the language? You can make as many "rules" as you want (that's what Vietnamese grammarians like to do) but the natives will break them without really trying. Examples sentences will illustrate what to do... and more importantly, what not to do.
Let me give another example. This time, I'll use phrasal verbs. For those that don't know, phrasal verbs are basically "verb + preposition". They are common in English. You use them without thinking. Unfortunately, they are painful for learners. There are "rules" for using them, and there are "rules" for not using them, and these "rules" are arbitrary and inconsistent for outsiders. Take as an example: "get on". You get on a plane. You even get on a bus. But you never get on a car, unless you like to ride the roof. You get in a car.
A good dictionary would show examples of what to do and what not to do. A bad dictionary (and these electronic dictionaries are bad) would just provide a translation of the word - say "trèo lên" for "get on" or "đến" for "get in". So students continue to produce wrong English, such as "I get on my parent's car. I sit in the passenger's seat."
Let me bring up the matter of pronunciation keys - another area where these gadgets let learners down. Since the the relationship between English spelling and pronunciation is capricious and uncaring, you need pronunciation keys for English words so that you can "read off" the pronunciation. The industry standard for pronunciation keys in the ESL world is the IPA - the International Phonetic Alphabet. It is what I was taught in my CELTA, and it is what both the Oxford and Cambridge dictionaries use. The problem is that while electronic dictionaries provide pronunciation keys for English words, these keys are often wrong. I don't even know what standard the makers are using, or even if the makers are even interested in standards at all. I suspect their primary motivation is in shifting units.
Let's take an example: how do you pronounce "grape"? A good dictionary would use IPA, and write /greIp/. These electronic thingamabobs seem to alternate between writing /greip/ and /grep/. Both are wrong. The first (/greip/) fails to distinguish between "I" and "i", but these are separate, distinguishable vowels in English. (For example, there's bit /bIt/ versus beet /bi:t/.) Alas, distinguishing these vowels are one of the big problems for Vietnamese learners - these vowels should be shown differently. As for /grep/, that is even worse. The vowels in "Grape" are a diphthong - two different vowels run together. Good transcriptions should show this. Using /grep/ seems to mislead my learners into pronouncing grape as a single vowel... a little bit like "grêp". It's close, but it's not quite right.
Some models come with a voice button. You can hear the word "spoken". Unfortunately, the sound is often so distorted that this feature is worse than useless. Anyone remember the old arcade game Gauntlet? With the narrator saying lines such as "Wizard needs food badly"? Then you get an idea of what noises these machines produce.
My aversion to electronic dictionaries is shared by other teachers. There are those who will ban them in class outright. Others will warn the students of their dangers. And me? For advanced students, I recommend that they buy themselves a good, monolingual dictionary such as the Cambridge Advanced Learner's Dictionary. It's big, it has accurate phonetic transcriptions, it comes with example sentences, and best of all - it's a lot cheaper. Even with a CD-ROM, it's only £19.85. If they can't afford to buy the book, learners can afford to access the website - they can do dictionary lookups online. (So can you; just use that link.) For less advanced learners, I have no problem with using the bilingual paper dictionaries available locally. They're not always accurate either, but they seem to be more accurate that the electronic dictionaries... and they're even less expensive. Pulp gives you extra advantages - you can scan down the page, and pick up related definitions with a flick of your eyeball. I think it's better that my lads and lasses pry open the pages of a book.
Better than using electronic dictionaries - those exorbitant, inaccurate, dangerous... toys.
 To be 100% accurate, there should be a minuscule capital "I" there, like "/greɪp/". But font support for IPA is pretty patchy on the Interweb, and IE users may see a meaningless box in its place. Hence the substitution. My apologies for any inaccuracies.