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"Certain" is an adjective which is often translated as "seguro", and "as well as" is a phrase which is often translated as "además de". Learn more about the difference between "certain" and "as well as" below.
certain(
suhr
-
tihn
)An adjective is a word that describes a noun (e.g., the big dog).
1. (definite)
a. seguro
What is certain is that technology will keep advancing.Lo que es seguro es que la tecnología seguirá avanzando.
2. (convinced)
a. seguro
I can't be completely certain, it's just a suspicion.No estoy completamente segura, es solo una sospecha.
3. (particular)
as well as(
ahz
wehl
ahz
)A phrase is a group of words commonly used together (e.g., once upon a time).
a. tan bien como
I could never play soccer as well as my brother can.Nunca pude jugar al fútbol tan bien como puede mi hermano.