What spelling pattern signals that the vowel in a first syllable will be short?

The most common spelling pattern that signals a short vowel sound in the first syllable is a closed syllable.

Here's what that means:

* Closed syllable: A syllable that ends with a consonant.

For example:

* cat (the vowel "a" is short because the syllable is closed by the consonant "t")

* dog (the vowel "o" is short because the syllable is closed by the consonant "g")

* spin (the vowel "i" is short because the syllable is closed by the consonant "n")

Exceptions:

* Some words with two consonants after the vowel: These can have a long vowel sound, like "coat", "boat", "hope".

* Words with "r" after the vowel: These can have a different vowel sound, like "car", "bird", "fern".

Remember, these are just general rules, and there are always exceptions. But understanding closed syllables is a good starting point for figuring out vowel sounds in words.