I eat an apple.
一般现在时I ate an apple.一般过去时
I will eat an apple.一般将来时
I would eat an apple.过去将来时
I will be eating an apple.一般将来进行时
I would be eating an apple.过去将来进行时
I shall have been eating an apple.一般将来完成进行时
I would have been eating an apple.
过去将来完成进行时I shall have eaten an apple.一般将来完成时
I would have eaten an apple.过去将来完成时
I am eating an apple.
现在进行时I was eating an apple.过去进行时
I have eaten an apple.
现在完成时I had eaten an apple.过去完成时
I have been eating an apple.
现在完成进行时I had been eating an apple.
过去完成进行时