A microscope is an optical instrument composed of a lens or a combination of several lenses, and is a sign that mankind has entered the atomic age. It is mainly used to magnify tiny objects into instruments that can be seen by human eyes.

Early education is the early education for children. Education before the age of 0-6 can become early education.

Educational toys include traditional Rubik's Cube, geometric building blocks, clay DIY and high-tech electronic products, etc., which are mainly suitable for elementary school and child education.

The samples collected for the new coronavirus nucleic acid test are called swabs. The full names of the two methods are the oropharyngeal swab and the NASOPHARYNGEAL Swab, respectively.

The safety of the experiment must always be paid attention to. Secondly, the course experiment is generally safer, and the connected fume hood does not enter the type (of course because there are not so many fume hoods).