would you show me usages of the verb should in conditional type 2 and third –

Question

My profs. has told me the fact that we could use the verb should as to conditional sentences" second and third", that is, probable and impossible sentences:

So, would you show me these, using the verb should?

Answer 1

It's grammatically correct to use "should" instead of "would" for the pronouns I/we in conditional type 2 and type 3 sentences, but the use of "would" is more common and that of "should" is seldom. A few examples are given below:

• If I worked harder, I would/should pass the exam. (type 2)

• If I had worked harder, I would/should have passed the exam. (type 3)

• if we had lots of money, we would/should travel round the world. (Type 2)

• If we had had lots of money, we would/should have travelled round the world (type 3)

Answer 2

Though as a student I was never encouraged to classify conditional sentences into three categories as you have mentioned in your question, I still know what they are. As a student I had learned various pattern with if-conditional sentences.

Conditional sentences are classified into the following -

1. Zero Conditional -

We use the zero conditional to talk about things that are always true.

Examples -

If you heat water, it boils.

2. First Conditional -

We use the first conditional when we talk about real and possible situations. In first conditional sentences, the structure is usually if + present simple and will + infinitive. It’s not important which clause comes first.

Examples -

I’ll go shopping on the way home if I have time.

3. Second Conditional -

The second conditional is used to talk about ‘unreal’ or impossible things. The structure is usually if + past simple and would + infinitive. It’s not important which clause comes first.

Examples -

If I won a lot of money I’d buy a big house in the country.

4. Third Conditional -

Third conditional sentences describe the past. They describe something that didn't happen. In third conditional sentences, the structure is usually if + past perfect and would + perfect infinitive (e.g. have done). It’s not important which clause comes first. Notice that other modal verbs can be used instead of ‘would’ (e.g. ‘could’, ‘might’ ‘may’)

Examples -

If I’d studied harder at school I would have gone to university.

5. Mixed Conditional -

In mixed conditional sentences the time in the ‘if’ clause is not the same as the time in the main clause. There can be various combinations.

Note

Although many conditional sentences use if + will/would, conditional sentences can also use other words instead of ‘if’ – e.g. ‘when’ ‘as soon as’ ‘in case’ Other modal verbs can be used instead of ‘will/would’ – e.g. ‘can/could’, ‘may’ ‘might’.

I have copied all these written above from the following links.

Link 1

Link 2

Please visit these two links for further studies. And also it's advisable to learn the pattern of conditional sentences. Please follow a good grammar book, if you want I can suggest one for you. The link I have provided is sufficient, but leaves a lot of questions to the mind of a learner of English as a second language.

You can follow Practical English Usage by Michael Swan (From page 245 to page 253)

As for your question about the conditional with "should", please visit this answer.