He was walking along the sands _______ hesaw a big foot-print in the sand .

is not an important element in bread, but flour is .

Let’s ______ a magazine and a novel for Tony’s birthday, OK— Great idea!

Her brother ______ be at home now, because he was seen playing basketball in the stadium just now.

Be quiet, Mr. Smith is coming.—Don’t worry. It ＿＿＿ be him. Mr. Smith is muchtaller.