On the days of the month that include a 5, (meaning the 5th, 15th and 25th of the month), you can get 5 times the points. Therefore you should add to the cart in advance.
ご質問ありがとうございます。
この場合、「毎月5のつく日はポイント5[倍](https://eikaiwa.dmm.com/uknow/questions/54703/)。事前にカートに入れておく」と言いたいなら、英語で「On the days of the month that include a 5, (meaning the 5th, 15th and 25th of the month), you can get 5 times the points. Therefore you should add to the cart in advance. 」と言えます。
ご参考になれば幸いです。
Every month on days that have a 5 in them, you get five times the points. Put in cart before hand.
"毎月5のつく日はポイント5倍。事前にカートに入れておく"
- Every month on days that have a 5 in them, you get five times the points. Put in cart before hand.
あるオンラインストアは、毎月5のつく日（5日、15日、25日）はポイント5倍です。だからそれらの日にお得にお買い物するために、事前に欲しいものをカートに入れておきます。
- An online store gives five times the points on days that have a five (5th, 15th, 25th). So in order to get the best deal on those days, I put what I want into my cart before hand.
アメリカ合衆国 
