Everyone will go through life's stages of ups and downs, ________ selfrespect plays a key role in the maturity(成熟) of a person.
________ inthought,healmostranintothecarinfrontofhim.
I watched the plane go higher and higher until I lost _____ of it.
I usually take something to read when I travel by train _____I feel bored.
Out _____, with an apple in his hand.
Not until he met with the difficulty _______ the importance of group work.