Learn Russian: Март — хороший месяц.

In Russian, the present tense of the verb "to be" (am, is, are) is almost always skipped. When a sentence simply links one noun to another noun—like linking Март (March) to месяц (month)—a long dash is often used in writing to take the place of "is."

How do I know what gender to use for the adjective хороший here?

Adjectives must match the gender of the noun they describe. Here, the adjective describes месяц (month). Because месяц ends in a consonant (ц), it is a masculine noun, so the adjective must also be in its masculine form (хороший).

Why does the adjective хороший (good) end in -ий instead of the standard masculine -ый?

Usually, masculine adjectives end in -ый (like новый, meaning new). However, Russian has a strict spelling rule: you can never write the letter ы after certain consonants, including ш. You must use и instead. Because the stem of the word ends in ш, it is spelled хороший.

Why doesn't the letter я in месяц sound like a clear "ya"?