Just like the cornerstone is crucial to a building's structure, 'to be' is vital in English grammar. It exists in almost every conversation, essay, or poem. The verb 'to be' is the most protean of all verbs, adorning itself in different forms such as 'is', 'am', 'are', 'was', 'were', and 'will be'.
In English, we use the verb 'to be' to denote states, characteristics, or identities. For instance, when we say, 'She is a teacher', we're using 'is' to establish identity. Likewise, 'I am happy' uses 'am' to express a state or condition, and 'You are tall' uses 'are' to describe a characteristic.
Interestingly, the verb 'to be' has deep roots in the history of the English language. Its various forms originate from Old English, and its usages have evolved over centuries. Despite these changes, its fundamental role remains the same, making it a resilient cornerstone of English grammar.
This versatile verb is an artifice that holds the English language together. So, next time you use 'is', 'am', or 'are', remember, you're using the most adaptable, historical, and essential verb in the English language.