"to be cognizant of" is correct and usable in written English.
It means to be aware of or knowledgeable about something. For example, "It is important to be cognizant of the dangers of drug abuse."
"We've got to be cognizant of that.
You have to be cognizant of your time.
"You've got to be cognizant of the tempo," Ryan said, "but you've got to be cognizant of what you're seeing".
"Growing up on a farm, you learn to be cognizant of your costs," he said.
We simply do not know what it means to be cognizant of the world around us.
We have to be cognizant of the moles; we want the moles to be comfortable, too.
"We want to put people on notice to be cognizant of their activities behind the wheel".
Any critique offered has to be cognizant of changing racial dynamics and class structures after globalisation.
Today, he said, "the space and the furniture have to be cognizant" of it almost instantly.
They will always have to be cognizant of what they eat.
"You have to be cognizant of price because students don't have access to funds".
