The language of negotiation makes ample use of conditional sentences, most frequently following the pattern of the first (If you do this, we will do that.) and second (If you did this, we would do that.) conditional.
When we use first conditional sentences, we talk about a present or future situation which (we think) is quite likely to happen and about its results or consequences.
if + present tense (simple, continuous, perfect) – will + infinitive
If you order more than 50 units, we will give you a 20% discount.
If I don’t get a promotion, I will leave the company.
We will open the shop earlier, if people are queuing for the new smart phone.
If my boss hasn’t called the new supplier, I’ll have to do it instead.
if + present tense – may, might, could, should
If you’ve been quoteda lower price, we might (may, could, should)consider another solution.
When we use second conditional sentences, we talk about a present or future (more or less) imaginary situation which (as we see it) is not very likely to happen and about its results or consequences.
if + past tense (simple, continuous) – would + infinitive
If we accepted your proposal, we would incur a substantial loss.
I wouldn’t be cross with your report if it were written properly.
if + past tense – could, might
If we saw more cooperation on your side, we could (might) grant you more favourable conditions.
Instead of if, it is possible to use other linking expressions: provided, as long as, on the condition that, supposing, in case, unless.
We will grant you a free delivery, provided (that) you agree to place another order with us.
(Only if you agree.)
I’ll buy some more tea in case we run out of the office supply. (I want to avoid running out of tea.)
They will charge us extra fees unless we pay in time. (If we don’t pay in time.)
You think something is possible, but you are not sure enough.
We may (could, might) be running into a big problem with this supplier.
I think Larry could (might, may) be already in the office.
You are sure that something is true.
We can’t be running into a problem with this supplier, they are quite reliable.
Larry must be in his office already, I saw him a minute ago.
He is in the office. (I know it, it is a fact.)
He must be in the office. (I think it is almost certain.)
He might be in the office. (I think it is possible.)