The professor could hardly find enough grounds on which to base his arguments ______ the new theory.
Our school, which has 10000 students, ____ on the bank of the An chang River.
Every student and every teacher ______.
I first met John at my sister’s wedding. He ____ with the bridegroom at the time.
— Have you any letters _____? — No, thanks.
---- Shall I give you a ride as you live so far away? ---- Thank you. ______.