Nowadays, teachers tend to be more dependent on _______ is thought to be a great teaching aid---the computer．
A．that B．which C．what D．as
Whenever I met her, _________ was fairly often, she greeted me with a sweet smile．
A．who B．which C．when D．that
---Can I keep the book any longer?
---Yes, but it _______ be renewed when time is due．
A．shall B．need C．will D．can
To ______ good relationships with your teachers and classmates, you should learn to be on good terms with them．
A．bring up B．add up C．keep up D．take up
Your article must be sent by e-mail _______ it can meet the deadline．
A．or else B．for fear that C．in case D．so that
Darkness _________, so we had to stop our journey and stayed on a farm for the night．
A．fell B．spread C．broke D．happened
