支test tube應該保持垂直既英文?

The test tube should maintain vertically.

The test tube should be kept in vertical position.

1) The test tube should be placed upright.

2) The test tube should be in an upright position.

3) The test tube should be placed perpendicularly.

希望可以幫到你 :)

YOU SHOULD KEEP THE TESTTUBE VERTICALLY,OR;

YOU SHOULD KEEP STRAIGHT THE TESTTUBE

the testube should keep vertical