1, shù, can be combined into compound words: mathematics, quantity, numbers, luck, etc.

2, shǔ can be combined with words: counting, unclear, counting, counting and so on.

The basic explanation of "countless":

Countless

The basic explanation of "counting";

Number, quantity, noun.

The basic explanation of "criticism";

It is also difficult to list mistakes to blame.

The basic explanation of "number theory";

Scold; Scold.

The basic explanation of "mathematics";

The science of studying the spatial form and quantitative relationship of the real world.

The basic explanation of "quantity":

How many things.

The basic explanation of "number":

Numbers; Symbol representing numbers

The basic explanation of "Qi number";

Fate, fate: heaven.