firm, tight (esp. AmE)
She felt a firm grasp on her hand.

slip from
As she jumped forward, the ball slipped from her grasp.

escape, slip out of (usually figurative)
He slipped out of our grasp (= he escaped).

prise sth from (BrE), pry sth from (esp. AmE), rip sth from, snatch sth from, wrench sth from, wrest sth from
She wrenched the bottle from his grasp.

tighten (esp. AmE)

beyond your grasp
The key was on a high shelf, just beyond her grasp.

in your grasp
He kept the letter firmly in his grasp.

from sb's grasp
The robber tried to free the case from her grasp.

out of sb's grasp
She kicked the gun out of his grasp.

within (your) grasp (often figurative)
Just when victory seemed within grasp, the referee blew his whistle.

firm, good, impressive, solid, strong
feeble, limited, poor, shaky, tenuous
intellectual
The task was beyond the intellectual grasp of some of the students.

intuitive
We have no intuitive grasp of the immensity of time.

have
get
Working with native speakers helped me get a good grasp of the language.

beyond sb's grasp
These ideas are all beyond his grasp.

within sb's grasp
grasp of
a poor grasp of mathematics

firmly, tightly

at
Her hands were grasping at his coat.

by
She grasped him tightly by the wrist.

grasp hold of sb/sth
She grasped hold of the banister to support herself.

fully
He had not fully grasped the fact that he was the one who would pay for all this.

not quite, not really
I hadn't really grasped what they were talking about.

quickly
easily, readily
a means by which students can more easily grasp the basics of science

try to
be unable to, fail to
She failed to grasp the significance of these facts.

quick to
He was quick to grasp the basic principles.

be difficult to, be hard to
Some of these concepts are very difficult to grasp.

Grasp is used with these nouns as the subject:
hand

Grasp is used with these nouns as the object:
arm, basics, chance, complexity, concept, edge, elbow, end, enormity, essence, essentials, fact, fundamentals, hand, handle, hold, implication, importance, intricacy, magnitude, meaning, opportunity, rail, reality, rein, seriousness, significance, situation, subtlety, truth, wrist