词汇	clear sign
释义	clear sign 明确的标记
随便看	reference book/material reference book reading room reference books reading room reference books room Reference Book Stacks reference boresight reference boresight of antenna reference box reference bridge reference broadcast reference broadcast synchronization reference bulb reference burst reference burst phase reference bushing reference cable reference call reference capacitance reference capacitor reference capacity reference capillary reference card reference carding reference carrier reference carrier burst