He must have been a stranger to the town。

　　他當時一定是剛到這個鎮子。

　　He was reeling a little。 He must be very drunk。

　　他有點踉蹌。他一定醉得很厲害。

　　He must like her， or he wouldn't keep calling her。

　　他一定喜歡她，不然他不會老給她打電話。