考试

Pinyin: kǎo shì
Meaning：Exam
Sentence：他对考试成绩十分担心。He's on a knife-edge about his exam results.

More:

考：

Pinyin: kǎo
Meaning: To check; to verify; to test
Radical: 耂
Stokes: 6
Traditional: 考
Common words/Phrase:
考虑 [kǎo lǜ] 【to consider】
考试 [kǎo shì] 【exam】
考勤 [kǎo qín] 【check on work attendance】
考核 [kǎo hé] 【check up on】
考察 [kǎo chá] 【inspect】

试：

Pinyin: shì
Meaning: Test; to test; to try; experiment; examination
Radical: 讠
Stokes: 8
Traditional: 試
Common words/Phrase:
试验 [shì yàn] 【test】
试用 [shì yòng] 【try something out】
试题 [shì tí] 【test questions】
试卷 [shì juàn] 【examination paper】
试图 [shì tú] 【to attempt】