however
sin embargo/no obstante
Se usa para introducir una declaración que contrasta con algo dicho anteriormente
Ejemplos
(1). I was tired. However, I kept working.
Estaba cansado. Sin embargo, seguí trabajando.
(2). The task was difficult; however, she completed it.
La tarea era difícil; no obstante, ella la completó.
(3). He is young. However, he is very mature.
Es joven. Sin embargo, es muy maduro.