33. The oil in the cooker ___ heavy smoke, which made us in tears and difficult to open our eyes .
Elephants would __________ soon if man was allowed to shoot as many as they wish.
He hasn't slept at all for three days. __________ he is tired out.
No problem lasts forever. Storms always __________ the sun.
—What's the matter with her car? —It looks __________ the engine couldn't work.
He studied hard,__________ the exam.