A. Yusuf Ali:Translation:
You they say: "Why are not Signs sent down to him
from his Lord?" Say: "The signs are indeed with Allah.
and I am indeed a clear Warner." 3481

Muhammad Asad:Translation:
And yet they say, “Why have no miraculous signs ever been bestowed upon him from on high by his Sustainer?” Say: “Miracles are in the power of God alone; 49 and as for me - I am but a plain warner.”
3481 See last note. In the Qur'an, as said in verse 49, are Signs which should carry conviction to all honest hearts. And yet the Unbelievers ask for Signs! They mean some special kinds of Signs or Miracles, such as their own foolish minds dictate. Everything is possible for Allah, but Allah is not going to humour the follies of men or listen to their disingenuous demands. He has sent a Messenger to explain His Signs clearly, and to warn them of the consequences of rejection. Is it not enough?