必 不 可 少 bì bù kě shǎo : absolutely necessary; indispensable; essential

必 需 bì xū : essential; indispensable

必 要 bì yào : necessary; essential; indispensable; required

不 可 缺 少 bù kě quē shǎo : indispensable

不 可 逾 越 bù kě yú yuè : impassable; insurmountable; insuperable

不 通 bù tōng : be obstructed; be blocked up; be impassable; not make sense; be illogical; be ungrammatical

不 宜 bù yí : not suitable; inadvisable; inappropriate

殘 [残] cán : destroy; spoil; ruin; injure; cruel; oppressive; savage; incomplete; disabled

Big5: , Unicode: 6b98 (殘),
Links: MT, Cantonese, Ld, Chinese Language

貂 diāo : sable; marten

Big5: , Unicode: 8c82 (貂),
Links: MT, Cantonese, Ld, Chinese Language

黑 貂 hēi diāo : sable

可 擦 寫 kě cā xiě : erasable

可 擦 寫 可 編 程 祇 讀 存 儲 器 kě cā xiě kě biān chéng zhī dú cún chǔ qì : EPROM; Erasable programmable read-only memory

痡 pū : sick; disabled

Big5: 痡, Unicode: 75e1 (痡),
Links: MT, Cantonese, Ld, Chinese Language

使 得 shǐ de : usable; workable; feasible; doable; to make; to cause

死 sǐ : to die; inpassable; uncrossable; inflexible; rigid

Big5: , Unicode: 6b7b (死),
Links: MT, Cantonese, Ld, Chinese Language