он не знал, как поступил бы, если б

он не знал, как поступил бы, если бы был на моем месте

Результаты (английский) 1:

He did not know how would have acted if would have been in my place

Результаты (английский) 2:

He did not know what would do if he were in my shoes

Результаты (английский) 3:

he didn't know what to do if you were in my shoes