William six books，and all of them are bestsellers.（ ）
A．will writeB．is writing
C．has writtenD．was writing
﹣﹣﹣Oh，I forgot to bring my umbrella．
﹣﹣﹣I've got one．You can share ______．（ ）
A．yoursB．oursC．mine
﹣﹣﹣Is that your headmaster？
﹣﹣﹣You mean the man ______ blue？（ ）
A．onB．withC．in
There ______ a large bowl of jiaozi on the table．（ ）
A．isB．areC．be
﹣Karl Marx is a great thinker． Do you know ？
﹣In 1818．（ ）
A．where he was from
B．when he was born
C．how he learned foreign languages
Yuan Longping is a Chinese rice scientist is leading a search to develop "sea rice"．（ ）
A．whoB．whichC．whom