吃透英语课本，提升在校竞争力
v. 证明；保证；证实
现在分词：certifying
第三人称单数：certifies
过去式：certified
过去分词：certified
She was certified as a teacher in 1990.
她于1990年获得教师资格证书。
The accounts were certified by an auditor.
这些账目经审计员核实过。
v.证明；保证
seal of
give evidence of
