[Grammar] would have/would has

[Oceanlike]

Although the subject is singular, why the answer isn’t ‘has witnessed’ but ‘have witnessed’

Jay would have witnessed the robbery had he taken the usual route home this morning.

Thank you for teaching me! :-D

 

[gurpreetgill4u]

I am not a teacher

It is an unreal conditional sentence,and we use would + infinitive.

Jay would have witnessed the robbery had he taken the usual route home this morning. = If jay had taken the usual route home this morning, he would have witnessed the robbery.

 

[kilroy65]

I am not a teacher

It is an unreal conditional sentence,and we use would + infinitive.

Jay would have witnessed the robbery had he taken the usual route home this morning. = If jay had taken the usual route home this morning, he would have witnessed the robbery.

This is a conditional sentence referring to the past; we use would/could/might+have+past participle in the main clause.