He dropped into an eloquent silence

He eludes analysis and baffles description

He glanced at her indulgently

He had the habit of self-engrossed silences

He harbored his misgivings in silence

He poured bitter and biting ridicule on his discomfited opponents

He spoke with sledgehammer directness

He suffers nothing to draw him aside

He took his courage in both hands

He turned on me a glance of stored intelligence

He was disheveled and untidy

He was inexhaustibly voluble

Heavily freighted with erudition [erudition = extensive learning]

Heights of serene contemplation

Her voice had a wooden resonance and a ghost of a lisp

Hidebound in official pedantry [pedantry = attention to detail]

High and undiscouraged hope

High-handed indifference to all restraint

His chin had too vanishing an aspect

His first zeal was flagging

His general attitude suggested an idea that he had an oration for you

His gestures and his gait were untidy

His mood was one of pure exaltation

His plea was irresistible

His tone verged on the ironical

His work was ludicrously perfunctory

Hopelessly belated in its appearance

I

I adjured him [adjured = command or enjoin solemnly, as under oath]

I am not without a lurking suspicion

I bemoaned my unlucky fate

I could almost allege it as a supreme example

I have somewhat overshot the mark

I lost myself in a reverie of gratitude

I made bold to retort

I must hazard the story

I was extremely perplexed

I will permit myself the liberty of saying

I would fain believe [fain = happily; gladly]

Illuminate with sinister effect

Immediate and effectual steps

Immense capacity for ceaseless progress

Immunity from criticism and control

Impartial and exacting judgment

Impatience of despotic influence

Impelled by strong conviction

Imperiled in a restless age

Imperious in its demands [imperious = arrogantly domineering]

Impotent outbreaks of unreasoning rage

Impromptu parades of noisy patriotism

In a diversity of application

In a fever of apprehension

In a frenzy of fussy excitement

In a frowning abstraction

In a great and fruitful way

In a high degree culpable

In a kind of confused astonishment

In a most commendable fashion

In a most impressive vein

In a position of undisputed supremacy