to add oil; to top up with gas; to refuel; to accelerate; to step on the gas; (fig.) to make an extra effort; to cheer sb on

to become a member; to join; to mix into; to participate in; to add in

to add; (math.) plus; to increase; to augment; (used before a disyllabic verb, often after an adverb like 不[bu4], 大[da4], 稍[shao1] etc, to indicate that the action applies to sth previously mentioned, as in 稍加改良[shao1 jia1 gai3 liang2] "make some minor improvements to (it)")

Canada (abbr. for 加拿大[Jia1 na2 da4]); surname Jia

more (than sth else); even more