問：「趕不上」或「跟不上」課程進度，英文怎麼說？
答：這個問題，最好還是用例句回答：（1）After a sickness absence of several months, he found it very difficult to catch up with the course（他因病缺席幾個月之後，發覺要趕上課程進度，十分困難）。（2）He was lazy and was unable to keep up with the progress of the course（他很懶惰，跟不上課程）。
問：最近收到通知說：You have not yet settled the application fee of your application on or before the payment deadline（閣下之申請費，於付款限期屆滿之前，還未收到）。句中的have not yet settled是不是應改為did not settle？
答：現在完成式動詞，說過去的事，一般不說明日期，否則宜用過去式。例如你昨天見過某人，可以說I have seen him或I saw him yesterday，但不宜說I have seen him yesterday。讀者示下那一句，既說明時間，自然應改用過去式You did not settle the application fee等等。
不過，用過去式，應是整件事已告一段落。假如還要討申請費，則句子可改寫如下：You have not yet paid / settled the application fee / the fee for your application, which was due on (date)（最遲須於某日期之前繳交之申請費，閣下還未付款）。這一句前半截用現在完成式，表示申請費至寫信時還未收到；下半截用過去式，表示日期已過。又原句application fee of your application當然是疊牀架屋說法。