入门不难，深造不易。

To cross the threshold is not difficult, but mastery is another question.

入门既不难，深造也是办得到的，只要有心，只要善于学习罢了。

To cross the threshold is not difficult and mastery, too, is possible provided one sets one's mind to the task and is good at learning.

总统对于国家安全是不需要读入门书的。

The President doesn't need a primer on national security.

这是对一门极为复杂的学科的有益入门教程。

It's a useful introduction to an extremely complex subject.

总而言之，这是一本通俗而务实的物理入门书。

On balance, the book is a friendly, down-to-earth introduction to physics.

几家公司正推出新的入门级产品，期望吸引更多的顾客。

Several companies are offering new, entry-level models in hopes of attracting more buyers.

可以说，这5个国家现在都已经通过了入门考试。

The five countries have now all passed, so to speak, their entry test.

这本书是科学的入门读物。

This book explains the ABC's of science.

他是我的入门师傅。

He is the master who initiated me into the craft.

我还没入门呢。

I don't even know the ABC of the subject yet.

他学汉语刚刚入门。

He has just learned the rudiments of Chinese.

有许多种很好的历史入门书。

There are many good~ s to history.

学英语入门并不难，学好可不容易。

Rudimentary English is easy to acquire, but mastery of the language is quite difficult.