XはYです

Here are the key points of this lesson:

• Omission of the subject (Xは)
• Using 'は' for clarity
• Nouns in Japanese”

Omission of the subject (Xは)

In Japanese, sentences often omit subjects when the context makes them clear, unlike in English where subjects like "I" or "it" are typically included. 

For example, "I am a student," "My major is Japanese language," and "It is 12:30" translate into Japanese as "がくせいです," "にほんごです," and "12じはんです," respectively, without direct subjects.

Using 'は' for clarity

If the context doesn't provide clarity, Japanese sentences can start with a topic marked by "wa" (は in hiragana), indicating "As for X, it is Y.”
For example,  “わたしは がくせいです" (As for me, I am a student), “せんこうは にほんごです" (As for my major, it is Japanese language), and "じかんは12じはんです" (As for the current time, it is 12:30).
The particle "wa" (は), used to denote the topic, differs from its usual pronunciation, "ha," except when used as a topic marker.

Additional Infomation

Nouns in Japanese

Additionally, Japanese nouns do not require articles like "a" or plural forms like "-s," making them context-dependent for singular or plural interpretation.