To pretty much enter anywhere nowadays you need to have gotten a Covid test within 72 hours (although it's unclear on whether or not this will change back to 48). Trying to calculate and plan when you need to get your next test can be a bit of a headache. However, one netizen came up with a handy little poem to help you remember which day you’ll need to get your next test. 

Not only is it great for remembering, it's also a nice little way to practice Chinese that isn't as hard as most of the tongue twisters we learned in Chinese class -- anyone ever master that Shi Shi Shi one? -- so, here's the 72 Hour Test Forumula:

72小时核酸检测口诀 72 xiǎo shí hé suān jiǎn cè kǒu jué

周一做，周一做，周一做完周四做；zhōu yī zuò ， zhōu yì zuò ， zhōu yī zuò wán zhōu sì zuò ；
周四做，周四做，周四做完周日做；zhōu sì zuò ， zhōu sì zuò ， zhōu sì zuò wán zhōu rì zuò ；
周日做，周日做，周日做完周三做；zhōu rì zuò ， zhōu rì zuò ， zhōu rì zuò wán zhōu sān zuò ；
周三做，周三做，周三做完周六做；zhōu sān zuò ， zhōu sān zuò ， zhōu sān zuò wán zhōu liù zuò ；
周六做，周六做，周六做完周二做；zhōu liù zuò ， zhōu liù zuò ， zhōu liù zuò wán zhōu èr zuò ；
周二做，周二做，周二做完周五做；zhōu èr zuò ， zhōu èr zuò ， zhōu èr zuò wán zhōu wǔ zuò ；
周五做，周五做，周五做完周一做；zhōu wǔ zuò ， zhōu wǔ zuò ， zhōu wǔ zuò wán zhōu yī zuò ；
周一做，周一做，周一做完周四做；zhōu yī zuò ， zhōu yì zuò ， zhōu yī zuò wán zhōu sì zuò；

72 Hour Testing Formula

Do it Monday, do it Monday, do it Monday and then do it Thursday;
Do it Thursday, do it Thursday, do it Thursday and then do it Sunday;
Do it Sunday, do it Sunday, do it Sunday and then do it Wednesday;
Do it Wednesday, do it Wednesday, do it Wednesday and then do it Saturday;
Do it Saturday, do it Saturday, do it Saturday and then do it Tuesday;
Do it Tuesday, do it Tuesday, do it Tuesday and then do it Friday;
Do it Friday, do it Friday, do it Friday and then do it Monday;
Do it Monday, do it Monday, do it Monday and then do it Thursday.

Now, see if you can say it ten times fast without messing up the tones. What's your favorite Chinese tongue twister? Let us know in the comments!