BIP39 proposed a hierarchical derivation scheme which uses "path" to distinguish different levels. Another proposal, BIP44, defines the specification of the path.
Remember to choose the correct path when importing mnemonics, because the same mnemonic will infer different addresses through different paths.
How to modify the import path:
When importing the mnemonic, you can open the advanced mode and change the path.
The default path of imToken is the same as the general standard of the community, thus users do not need to modify it when importing mnemonics.
If you modify the import path, it is very important to keep it in mind for if you forget the path, you may lose your assets.