You can choose any articulation by keyswitching, using the Articulation Chooser, or with automation.

The Articulation Chooser

LIST OF ARTICULATIONS
Long Notes - Infinite sustain (looped)
Normal - Bow moves in normal "arco" style, and left hand fingering is fixed on one note.
Legato (with multiple layers for blending or selecting vibrato/dynamics)
Accent pp (Adds a soft accent to Legato. Choose from 6 different accent styles.)
Accent mf (Adds a somewhat loud accent to Legato. Choose from 6 different accent styles.)
Accent ff (Adds a loud accent to Legato. Choose from 6 different accent styles.)
Adagio (same as "Legato" but much slower)

Short Notes
Choose "Short Notes, and then Accent pp, Accent mf, or Accent ff to hear only the accent part of a note.

Accent Styles
Marcato (or Staccato) - Aggressive attacks. Good for heavy, robust and assertive passages. Works well playing in a "staccato" style as well.
Detache - A more even attack than "Marcato". Good for bringing out bow changes between notes.
Spiccato - Played with the bow bounced off the string. Good for lively, playful passages.
Marcato Molto - More aggressive than Marcato.
Detache Molto - More aggressive than Detache
Spiccato Molto - More aggressive than Spiccato.

Various Effects (FX) - Either bowing or left hand fingering is different than "Normal" above.
Tremolo
Half Step Trill (Only available in the full version of (Concert Strings II).
Whole Step Trill (Only available in the full version of (Concert Strings II).
Pizzicato
Bartok Pizzicato (Only available in the full version of (Concert Strings II).
Harmonics (Only available in the full version of (Concert Strings II).