文字造字的方法主要有六种，排在第一位的是（）。A、假借 B、形声 C、会意 D、象形

—Must I finish my homework right now? 

-- No, you ___, you ___finish it tomorrow morning.

A．mustn’t, can

B．needn’t, must

C．don’t have to, may

D．can’t, have to

女，35岁，常有胸闷，头颈部搏动感，体检心脏闻及病理性杂音，脉压增宽，有毛细血管搏动征。

根据周围血管体征，关于诊断考虑错误的是（）。

A.主动脉瓣关闭不全

B.甲状腺功能亢进

C.严重贫血

D.动脉导管未闭

E.室间隔缺损

大黄牡丹汤的功用是

A．攻下热结，理气活血

B．泻热破瘀，散结消肿

C．泻热逐水，活血化瘀

D．攻下热结，凉血止血

E．泄热通便，活血消肿

远古神话

In a public-key cryptosystem, (71) encrypted with the public key can only be deciphered with the private key from the same (72) . Conversely, (71) encrypted with the private key can be decrypted only with the public key. Users can make their public keys (73) available or place them at a key distribution center or others to access. However, the private key must be (74) safe. In public-key systems there’s no (75) to find a safe channel for communicating a shared secret key.

A. more B. necessary C. need D. space