Staying awake ______ taking online classes is hard. Airwaves can help! 線上上課時要保持清醒是很困難的;好在 Airwaves能幫忙! a. in b. on c. when d. through 嚼對專注,終結分心,來兩粒Airwaves~ https://bit.ly/2YvRilq 解析: 本題測驗的是分詞構句之用法;以when taking取代原來的when you are taking或when you take,因此正確答案為C。 (A) 在…中 (B) 以…方式 (C) 當…時 (D) 透過… Chinese translation After leaving this page, need to use 1 more coin to play audio Sorry! You don't have enough coins.