Would you lend me your pen for a while？ —Certainly. I _____.

I want to go to the party, but ______I ought to be studying[ ]

The girl has a great interest in sport and ________ badminton classes twice a week over the last three years.

You will succeed in the end _______ you give halfway.

________is well known to everyone，I should say，is that a man becomes learned by asking questions.