【C6】A．sinceB．whileC．whereasD．before

【25】A．soB．whateverC．whereasD．however

【C18】A．thoughB．whileC．beforeD．until

【24】A．providedB．sinceC．whereasD．though

【24】A．IfB．AlthoughC．WhereasD．Because

【C5】A．SinceB．After a whileC．AgainD．Before long

You’ll have more chances of promotion ______ you work hard.A、sinceB、whileC、asD、once