Learn Russian: Апрель и май — весна.

In Russian, the present tense of the verb "to be" (am, is, are) is almost never used. When you link two nouns together, like the months and the season in this sentence, you use a long dash (—) in writing to take its place.

Why is май written with a lowercase letter?

Unlike in English, days of the week and months of the year are not capitalized in Russian. Апрель is only capitalized here because it is the very first word of the sentence.

How do I know if Апрель is masculine or feminine since it ends in a soft sign (ь)?

Nouns ending in a soft sign (ь) can be either masculine or feminine, so you often just have to memorize their gender. However, a helpful trick is that all months of the year in Russian, including Апрель, are masculine.

Why isn't there a word for "the" before весна?

Russian does not use articles like "a", "an", or "the". Depending on the context, весна can mean "spring", "a spring", or "the spring". Here, it just translates to "spring".