Much of our spoken language is simply 'running off' key phrases, and this significantly reduces our cognitive load. It means we are able to use language more fluently, and to have capacity left over for organising higher level processes.
As there are many thousands of words, and each phrase has many words, the number of potential phrases is enormous - probably many billions.
However, we actually only use relatively few of these, and some are quite common.
Phrases vary by how close their meaning is to the actual words involved. Most can be worked out easily, but a relatively small number are idiomatic (e.g. je vous en prie). Some of these don't translate easily and are usually only mastered by native speakers.
Unfortunately, there doesn’t seem to be a list of phrases, sorted by their frequency. This means that the best bet to identify the most common/useful ones seems to be to use the ‘phrase book approach’. That is to say, to cover the key areas of life that one is interested in (such as going to a restaurant/shop/station etc), then to focus on the main phrases which seem likely to cover the key processes there.
The ones used on this page are a sample of a few categories.
Now record your own voice and listen to the playback - check for any differences
Repeat until they sound the same
A powerful technique is to play the word/phrase, and to 'shadow' - say the word/phrase out loud at the same time as you listen to it. Do this a number of times (until you feel confident), then go straight on to record.
As soon as you think that you are able to copy accurately, record and listen to your own voice first, then only check if you feel you need to.
Once you get the main pronunciation right, try to get the overall rhythm and tonality the same as well. In French, the main word emphasis is usually on the last syllable of the last word in each phrase.
It can often be a good idea to try a tricky word/phrase in your head a few times, before recording.
The time available for you to make the recording is set at normal talking speed, plus a small amount extra. When you are fluent with the word you will not need all of this.
When you listen to the word/phrase, a translation is also briefly shown below the buttons. This is only there as a reminder for you to check if you wish.
The speed adjustment gives you three levels:
Slow - for starting out, and when you are having problems with particular sounds.
Normal - this is close to formal speeches and will be used when people know that you are not French.
Fast - this is close to normal, conversational French. It is worth aiming for this as it's a form of 'over-rehearsal'. When you can do something fast, then it becomes automatic and you're less likely to regress.
Incidentally, it does seem true that French is normally spoken 16% faster than English. This appears to be due to the fact that French has a lower informational density, so you need to talk faster to get the same information across (Pellegrino et al 2011).