书上说的没错。当副词much 修饰动词时，通常只用于否定句或疑问句，一般不用于肯定句，除非其前有 very, too, so 等之类的修饰语。如：

正：He doesn’t like her much. (用于否定句，对)

正：He doesn’t much like her. (用于否定句，对)

正：Does he like her much?(用于疑问句，对)

正：Does he much like her?(用于疑问句，对)

正：He likes her very [too, so] much. (有修饰语，对)

误：He likes her much. /He much likes her. (用于肯定句，无 修饰语，错)

但是注意，单个的 much 有时也能在肯定句中修饰动词。但这类动词只限于 regret, admire, prefer, appreciate 等个别动词，且只能放在句中，不可放在句末。如：

We much appreciate your invitation. 我们非常感激你的邀请。