In 1938, Hitler _________ war against Poland, which started the Second World War.

Only by _______ your attention _______ what you are learning can you learn it well.

—I wonder how much you _______for your services. ---Well, the first two are free while the third costs $30 .

—Where is you pencilbox,Tom?—I’ve __________ it for this kite.

 My cousin doesn’t know what to ______ at the university; he can’t make up his mind about his future.