Sometimes it is

有时───Sometimes;它───it

Pipe smokers sometimes wear down the tips of their teeth where they grip their pipes.───抽烟斗的人用牙齿咬住烟斗，有时会把齿尖磨平。

Sometimes formal English and informal English must be carefully distinguished.───有时候正式英语与非正式英语要十分小心地加以区分.

Even friends disagree sometimes.───即便是朋友有时也有分歧。

Prejudice sometimes hampers a person from doing the right thing.───有时候,偏见会妨碍人正确行事.

People tend to amass possessions, sometimes without being aware of doing so.───人们倾向于积攒东西, 有的并未意识到这样做.

It was fatiguing sometimes to try to measure up to her standard of perfection.───有时候，力求达到她尽善尽美的标准让人觉得很累。

Sometimes she spoke sensibly; sometimes she rambled.───有时她讲话很有条理，有时则讲得漫无边际。

Delusions are sometimes insidiously destructive.───妄想有时也具有潜在的破坏性。